Yes, I'm on prednisolone and have heart issues (heart attack 8yrs ago and now regurgitating valves, not too serious), so I monitor and record blood pressure/heart rate every day. On the odd occasion that my heart rate drops to 40-42, usually accompanied by nausea, a strong heart beat or palpitations, I'm reminded to drink more water. Within an hour or so of drinking two large glasses the heart rate is always increased. Even before being on prednisolone, it would happen occasionally and was always to do with not drinking enough water.

Furosemide: I was taking this occasionally to reduce fluid till a year ago. It messed with my electrolytes and caused lower back pain (kidneys) when taken for more than a week so I am now instructed not to take it at all. To keep fluid retention under control and to protect the kidneys by giving them a good flush, I now drink extra water instead and eat low carbohydrate. I've had no fluid retention problems while on prednisolone.